1. Field of the Invention
The present invention relates to a video camera system for recording the video signal of a moving image to tape, disk, semiconductor memory, or other medium, and extracting from the moving image recorded on said medium the image representative of the moving image content.
2. Description of the Prior Art
FIG. 16 is a block diagram of a conventional video camera system described in Japanese Laid-open Patent Publication Number 4-220090, and comprising a video signal input terminal 101, electronic viewfinder 102, recording unit 103, line video output terminal 104, character generator 105, recording start trigger terminal 106, and timer circuit 107. As shown in FIG. 16, the character generator 105 superimposes a character pattern over the video signal, and outputs the composite signal to SW1. The timer circuit 107 sets switch SW1 to pole B1 for a predetermined time starting from the recording start trigger timing, and then switches SW1 to pole A1. As a result of this operation, the signal displayed, recorded, or output by the electronic viewfinder 102, recording unit 103, and line video output terminal 104 is the video signal to which the character pattern is superimposed for the predetermined timing from the recording start trigger timing, and then becomes a normal video signal with no superimposition.
In the video camera system described in Japanese Laid-open Patent Publication Number 2-214271, searching the recorded image is made possible by writing a reduced image of the imaged scene into a video memory each time the recording start trigger button is pressed.
With a conventional magnetic recording and reproducing apparatus as described in Japanese Laid-open Patent Publication Number 1-246973, it is possible to extract just the data signal for searching, editing, and other processes without damaging the video signal by recording a time code or other data signal multiplexed with the vertical blanking period of the video signal.
However, it is difficult to search for and find a frame representative of the content of the motion image from an image recorded by a video camera system thus comprised. For example, to find a frame to which a specific character pattern has been superimposed in an image recorded by the video camera system described in Japanese Laid-open Patent Publication Number 4-220090, it is necessary to first separate the character pattern from the video signal and then compare the separated character pattern with the character pattern to be found, a conceptually simple but technically difficult task to accomplish.
With images recorded using the video camera system in Japanese Laid-open Patent Publication Number 2-214271, it is only possible to search for the image captured at the moment the recording start trigger button was pressed. Because the frame captured at that instant is rarely the frame that is most representative of the image, the precision of searching for the representative frame is low.
In addition, the data signal recorded by the magnetic recording and reproducing apparatus described in Japanese patent laid-open number 1-246973 only indicates the time and frame number, and this information is insufficient for automatically locating the frame that best represents the image.